Conventionally, aromatic products (benzene/toluene/xylene) have been produced by hydrogenating and extracting pyrolysis gasoline, which is produced together with basic petroleum fractions such as ethylene, propylene and the like in a naphtha cracking center using naphtha as a raw material, or by preparing reformate from naphtha through catalytic reforming and then extracting the reformate therefrom.
However, this conventional method of producing aromatic products is problematic in that it cannot cope with the increase in demand because only naphtha, which is a petroleum fraction having a narrow boiling point range and produced by the ordinary distillation of crude oil, is used.
Fluid catalytic cracking (FCC) is a typical process of producing gasoline from heavy oil. Recently, more facilities for FCC have been established.
Examples of products produced by FCC include propylene, methyl tertiary butyl ether (MTBE), alkylates, light cracked naphtha (LCN), heavy cracked naphtha (HCN), light cycle oil (LCO slurry oil (SLO), etc. These products are respectively used as a raw terial for synthetic resin (PP), an oxygen-containing fraction for gasoline, a high-octane fraction for gasoline, a blending agent for gasoline, a blending agent for light oil/heavy oil, a blending agent for heavy oil, a blending agent for heavy oil, etc. Particularly, among these products, LCO can be used as an alternative to naphtha because it contains a large amount (70% or more) of aromatic components of one or more aromatic rings. However, LCO is not suitable as a raw material to be used in a conventional process of producing aromatic products using naphtha because heavy aromatic components of two or more aromatic rings must be converted into aromatic components of one aromatic ring and because catalyst poisoning components such as sulfur, nitrogen and the like must be treated.